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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The role of the major histocompatibility complex and the Leukocyte receptor complex genes in susceptibility to tuberculosis in a South African population

Salie, Muneeb 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Tuberculosis (TB) disease results in approximately 2 million deaths annually and is the leading cause of death due to a single infectious agent. Previous studies have indicated that host genetics play an important role in the development of TB. This together with pathogen and environmental factors intensifies the complexity of this disease. The Major Histocompatibility Complex (MHC) and Leukocyte Receptor Complex (LRC) comprise several genes which are known to be important modulators of the host immune response. The human leukocyte antigen (HLA) class-I genes of the MHC are involved in the presentation of pathogenic antigens on the surfaces of infected cells, while the killer cell immunoglobulin-like receptors (KIRs) of the LRC are involved in the recognition of self and non-self cells. Natural Killer (NK) cells through their KIRs are thus able to kill non-self cells through recognition of the class-I molecules expressed. Additionally, HLAs and KIRs are extremely polymorphic and differ markedly across populations of different ethnicities. Here we studied these genes and their polymorphisms in the South African Coloured (SAC) population to determine their involvement in susceptibility to TB, susceptibility to disease caused by specific Mycobacterium tuberculosis subtypes, and understanding their ancestral contribution to the SAC with regards to the development of TB. We showed that the KIR3DS1 gene and KIR genotypes with five or more activating KIRs, and the presence of 3DS1, protected against the development of active TB in the SAC population. Several HLA class-I alleles were identified as susceptibility factors for TB disease. With regards to genes of the MHC and LRC, several loci were found to alter susceptibility to TB in the SAC population, including MDC1, BTNL2, HLA-DOA, HLA-DOB, C6orf10, TAP2, LILRA5, NCR1, NLRP7 and the intergenic regions between HLA-C/WASF5P and LAIR1/TTYH1. We showed that the Beijing strain occurred more frequently in individuals with multiple disease episodes, with the HLA-B27 allele lowering the odds of having an additional episode. Associations were identified for specific HLA types and disease caused by the Beijing, Latin America-Mediterranean (LAM), Low-Copy Clade (LCC), and Quebec strains. HLA types were associated with disease caused by strains from the Euro-American or East Asian lineages, and the frequencies of these alleles in their sympatric human populations identified potential co-evolutionary events between host and pathogen. Finally, we showed that the SAC population is the most diverse SA population with regards to HLA alleles and KIR genotypes, as would be expected given the admixture of the SAC. Based on the HLA allele class-I profiles across SA populations, we noted that the Ag85BESAT- 6, Ag85B-TB10.4 and Mtb72f vaccines currently undergoing clinical trials would have low efficacy across most SA populations. We showed that the MHC and LRC regions in SAC healthy controls are predominantly of European ancestry, and that SAC TB cases are more closely related to Khoisan and black SA population groups. Our work highlights the importance of investigating both host and pathogen genetics when studying TB disease development and that understanding the genetic ancestral contributions to the SAC population can contribute to the identification of true and novel TB causing variants. / AFRIKAANSE OPSOMMING: Tuberkulose (TB) is jaarliks verantwoordelik vir ongeveer 2 miljoen sterftes en is die hoofoorsaak van dood as gevolg van „n aansteeklike siekte. Vorige navorsingstudies het aangedui dat die genetiese samestelling van die gasheer „n beduidende rol speel in die ontwikkeling van TB. Die kompleksiteit van hierdie siekte word vererger deur die betrokkenheid van die gasheer genoom sowel as bakteriële en omgewings faktore. Die Major Histocompatibility Complex (MHC) en Leukocyte Receptor Complex (LRC) bestaan uit verskeie gene wat die gasheer immuunrespons verstel. Die human leukocyte antigen (HLA) klas I gene van die MHC is betrokke by die aanbieding van patogeniese antigene op die oppervlak van geïnfekteerde selle, terwyl die killer cell immunoglobulin-like receptors (KIRs), geleë in die LRC, betrokke is by die herkenning van eie en vreemde selle. NK selle, deur middel van hul KIRs, kan dus vreemde selle uitwis aangesien hulle die uitgedrukte klas I molekules kan herken. Beide HLA en KIRs is hoogs polimorfies en verskil beduidend tussen etniese groepe. In hierdie studie is die bogenoemde gene en hul polimorfismes in die Suid Afrikaanse Kleurling bevolking (SAC) ondersoek om vas te stel tot watter mate dit genetiese vatbaarheid vir TB, asook vatbaarheid vir TB wat deur spesifieke Mycobacterium tuberculosis subtipes veroorsaak word, beïnvloed. Daar is ook gepoog om te verstaan hoe die voorouerlike bydrae van hierdie gene die SAC met betrekking tot TB vatbaarheid affekteer. Die resultate van die studie het aangedui dat die KIR3DS1 geen en KIR genotipes met vyf of meer aktiewe KIRs en die teenwoordigheid van 3DS1, die SAC bevolking beskerm teen die ontwikkeling van aktiewe TB. Verskeie HLA klas I allele is geïdentifiseer as vatbaarheidsfaktore vir TB. Talle lokusse van die MHC en LRC gene is ook as vatbaarheidsfaktore vir TB in die SAC bevolking geïdentifiseer, insluitende MDC1, BTNL2, HLA-DOA, HLA-DOB, C6orf10, TAP2, LILRA5, NCR1, NLRP7 en die intergeniese areas tussen HLA-C/WASF5P en LAIR1/TTYH1. Die studie het aangedui dat die Beijing stam meer voorkom in individue wat verskeie kere TB gehad het en dat die HLA-B27 alleel die kanse om „n verdere episode te hê, verlaag het. Assosiasies is geïdentifiseer tussen spesifieke HLA tipes en siekte veroorsaak deur die Beijing, LAM, LCC, en Quebec TB stamme. HLA tipes was geassosieer met siekte veroorsaak deur TB stamme van Euro-Amerikaanse en Oos-Asiëse afkoms. Die frekwensies van hierdie allele, in hul ooreenstemmende mensbevolkings, dui op „n potensïele koevolusionêre gebeurtenis tussen die gasheer en patogeen. Die studie het ook vasgestel dat die SAC populasie die mees diverse SA bevolking is met betrekking tot die HLA allele en KIR genotipes, soos verwag sou word gegewe die gemengde genetiese herkoms van die SAC. Gebaseer op die HLA allele klas I profiel van verskillende SA bevolkings merk ons op dat die Ag85B-ESAT-6, Ag85B-TB10.4 en Mtb72f vaksiene, wat huidiglik kliniese toetsing ondergaan, nie so effektief in die meeste SA bevolkings sal wees nie. Die studie het ook bewys dat die MHC en LRC streke in gesonde SAC kontroles, grootliks afkomstig was van „n Europese nalatenskap en dat die SAC TB gevalle meer verwant is aan die Khoisan en swart SA bevolkings. Hierdie studie beklemtoon die noodsaaklikheid om beide gasheer en patogeen genetika te bestudeer wanneer die ontwikkeling van TB ondersoek word en dat die verstaan van die genetiese voorouerlike bydrae van die SAC bevolking kan bydra tot die identifisering van ware en nuwe TB-veroorsakende variante.
42

Approche co-évolutive humain-système pour l'exploration de bases de données / Human-system co-evolutive approach for database exploration

Rajaonarivo, Hiary Landy 29 June 2018 (has links)
Ces travaux de recherche portent sur l'aide à l'exploration de bases de données.La particularité de l'approche proposée repose sur un principe de co-évolution de l'utilisateur et d'une interface intelligente. Cette dernière devant permettre d'apporter une aide à la compréhension du domaine représenté par les données. Pour cela, une métaphore de musée virtuel vivant a été adoptée. Ce musée évolue de façon incrémentale au fil des interactions de l'utilisateur. Il incarne non seulement les données mais également des informations sémantiques explicitées par un modèle de connaissances spécifique au domaine exploré.A travers l'organisation topologique et l'évolution incrémentale, le musée personnalise en ligne le parcours de l'utilisateur. L'approche est assurée par trois mécanismes principaux : l'évaluation du profil de l'utilisateur modélisé par une pondération dynamique d'informations sémantiques, l'utilisation de ce profil dynamique pour établir une recommandation ainsi que l'incarnation des données dans le musée.L'approche est appliquée au domaine du patrimoine dans le cadre du projet ANTIMOINE, financé par l'Agence Nationale de la Recherche (ANR). La généricité de cette dernière a été démontrée à travers son application à une base de données de publications mais également à travers l'utilisation de types d'interfaces variés (site web, réalité virtuelle).Des expérimentations ont permis de valider l'hypothèse que notre système s'adapte aux évolutions des comportements de l'utilisateur et qu'il est capable, en retour, d'influencer ce dernier. Elles ont également permis de comparer une interface 2D avec une interface 3D en termes de qualité de perception, de guidage, de préférence et d'efficacité. / This thesis focus on a proposition that helps humans during the exploration of database. The particularity of this proposition relies on a co-evolution principle between the user and an intelligent interface. It provides a support to the understanding of the domain represented by the data. A metaphor of living virtual museum is adopted. This museum evolves incrementally according to the user's interactions. It incarnates both the data and the semantic information which are expressed by a knowledge model specific to the domain of the data. Through the topological organization and the incremental evolution, the museum personalizes online the user's exploration. The approach is insured by three main mechanisms: the evaluation of the user profile modelled by a dynamical weighting of the semantic information, the use of this dynamic profile to establish a recommendation as well as the incarnation of the data in the living museum. The approach has been applied to the heritage domain as part of the ANTIMOINE project, funded by the National Research Agency (ANR). The genericity of the latter has been demonstrated through its application to a database of publications but also using various types of interfaces (website, virtual reality).Experiments have validated the hypothesis that our system adapts itself to the user behavior and that it is able, in turn, to influence him.They also showed the comparison between a 2D interface and a 3D interface in terms of quality of perception, guidance, preference and efficiency.
43

Phylogeny and evolution of a highly diversified catfish subfamily : the Loricariinae (Siluriformes, Loricariidae)

Covain, Raphaël 15 September 2011 (has links) (PDF)
The Loricariinae belong to the Neotropical mailed catfish family Loricariidae, the mostspeciose catfish family in the world, and are united by a long and flattened caudal peduncle and the absence of an adipose fin. Despite numerous works conducted on this group, no phylogeny is presently available. Prior to conduct evolutionary studies, an exhaustive and robust phylogeny was reconstructed using mitochondrial and nuclear data. Then, this phylogeny was used in multivariate and multi-table analyses to reveal the main evolutionary trends of the subfamily. The resulting phylogeny indicated that the Harttiini tribe, as classically defined, formed a paraphyletic assemblage and was restricted to three genera, and within the Loricariini tribe, two sister subtribes were distinguished, Farlowellina and Loricariina, both displaying complex evolutionary patterns. In addition several new taxa were highlighted and described. Subsequently using this phylogeny as exploratory tool, we demonstrated: (1) using co-inertia analysis that the diagnostic features provided to define the different genera were phylogenetically dependent; (2) using multiple co-inertia analysis that the underlying evolutionary forces shaping their diversification included intraphenotypic (morphology and genetics) and extraphenotypic (ecology and distribution) components; (3) using the RLQ analysis that co-dispersion events occurred between co-distributed species responsible for the current fish distribution; and (4) using the multi-scale pattern analysis that the co-evolution in traits related to the mouth characteristics was linked to reproductive functions responsible for a tertiary evolution of this organ.
44

Aposematism, Crypsis and Population Differentiation in the Strawberry Poison Frog

Rudh, Andreas January 2012 (has links)
Evolutionary transitions between the two major predator avoidance strategies aposematism and crypsis are expected to be associated with changes in many important traits of animals. However, empirical studies on populations experiencing ongoing or recent transitions between these strategies are rare. This thesis investigates the co-evolution of traits among populations of the Strawberry poison frog D.pumilio in Bocas del Toro, Panama. I found that all investigated populations were genetically distinct but that colour and pattern did not correlate with genetic or geographic distance, which suggests that selection needs to be invoked to explain the observed variation. Based on the chromatic contrast between frog dorsal colour and the natural habitat substrates used by the frogs, the populations were defined as bright or dull coloured. I found that frogs from bright coloured populations were larger. This is expected if aposematism is enhanced by large signals while crypsis is enhanced by small size. Further, individuals from bright coloured populations had a coarser black dorsal pattern, which is expected if crypsis is impaired by a bold pattern. The importance of pattern coarseness was confirmed by an avian detection experiment showing that coarse patterned dark green prey were more easily detected than dark green prey without pattern or with fine pattern. I put forward the hypothesis that enhanced protection, gained by aposematism, may affect behaviours that influence dispersal and pairing patterns. Indeed, males from bright coloured populations displayed at more exposed sites and showed a tendency to be more explorative and aggressive. In summary, my results show that the bright and dull coloured populations most likely represent an aposematic and a cryptic strategy, respectively. Furthermore, I show that evolutionary changes between aposematism and crypsis can be associated with coevolution of both morphology and behaviour. I argue that this coevolution may increase the likelihood of both pre- and post-zygotic reproductive isolation. This is because greater phenotypic differences between populations increase the likelihood of selection against badly adapted migrants and hybrids with intermediate traits.
45

Evolutionary interactions of brood parasites and their hosts : recognition, communication and breeding biology : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Auckland, New Zealand

Anderson, Michael Gareth January 2009 (has links)
Obligate brood parasites lay their eggs in nests of other species, relying on these host parents to care for their offspring. This phenomenon has been a curiosity amongst researchers since its first description and has become a model study system for testing such ideas as coevolution and species recognition. This thesis examines a few of the many questions that arise from this breeding system. The New Zealand Grey Warbler (Gerygone igata) and its brood parasite, the Shining Cuckoo (Chrysococcyx lucidus) are used as the main study species, although research on the eviction behaviour of Common Cuckoos (Cuculus canorus) has also been conducted. First, the current state of knowledge and recent discoveries regarding nestling rejection abilities of hosts is reviewed in chapter one. Second, a comparative study of New Zealand passerine begging calls has been conducted to test for begging call similarity between a brood parasite and its host, as well as developing a new technique for detecting the mode of coevolution that may be occurring in the parasite – host relationship. Parent-offspring communication in Grey Warblers is also examined to test for both parental and nestlings Parents use both alarm calls to warn offspring of potential danger, and also parental feeding calls to elicit a begging response from nestlings. By contrast, nestlings are able to signal both age and short term levels of need to parents through the acoustic structure of the begging call. The evolutionary costs and benefits of egg eviction behaviour in the Common Cuckoo are also tested. An experimental approach showed that egg eviction had a growth cost, but this cost was temporary and restricted to during and immediately after the egg eviction phase. A pattern of compensatory growth was observed after the eviction period, so that during the later nestling stages there was no difference in mass, and no difference in fledging age. Finally, variation in the Grey Warbler breeding biology and Shining Cuckoo parasitism rates are examined through both time and across latitudes. This research has shown a counterintuitive pattern of breeding phenology across latitudes. These patterns have implications for Shining Cuckoos both in terms of timing of available nests and host selection. Keywords: Begging call, breeding phenology, brood parasitism, coevolution, Common Cuckoo, eviction, Grey Warbler, parent-offspring communication, Shining Cuckoo.
46

Uma abordagem evolucionária de sistemas de relações de trabalho : o processo de co-evolução entre tecnologias e as instituições do trabalho

Costa, Rodrigo Morem da January 2014 (has links)
Esta tese estabelece uma abordagem evolucionária de sistemas de relações de trabalho (SRT- e), a qual consiste em propor uma ferramenta analítica que possibilite estudar as mudanças em sistemas de relações de trabalho ao longo do tempo como um processo evolutivo movido pelos avanços tecnológicos. Para esse intuito, o modelo de SRT desenvolvido por John Dunlop foi tomado como base, sendo modificado para compatibilizá-lo com as contribuições da Teoria Evolucionária. A alteração foi feita no sentido de tornar endógena ao modelo as fontes de geração de variedade no SRT desenvolvido por Dunlop, através de uma maior centralidade da firma, como aquela que desenvolve e introduz novas tecnologias na economia para obter vantagem competitiva em seu processo de concorrência no mercado, e da alteração na concepção do contexto do sistema de relações de trabalho. Desse modo, a mudança proposta permite que o nexo entre tecnologias físicas, rotinas organizacionais (tecnologia social), formas de regulação das relações de trabalho constantes nas regras (tecnologia social) e a teia de regras do SRT-e (instituições) seja estabelecido, consistindo no uso da “ponte” entre tecnologias e instituições, conforme sugerida por Richard Nelson. Com base na ferramenta de análise de SRT-e, o esforço teórico da tese foi, também, o de identificar como ocorre o alinhamento entre as inovações tecnológicas de um novo paradigma tecno- econômico e as instituições das relações de trabalho. Para tanto, foi explorada a ideia da “ponte” proposta por Richard Nelson, identificando do ponto de vista teórico, como ocorre a compatibilização entre as tecnologias e as instituições das relações de trabalho, que se constitui em um dos principais alinhamentos ao pleno estabelecimento de um novo paradigma tecno-econômico, ao permitir a efetividade de exploração do potencial de desenvolvimento econômico de um dado país. A proposta da tese está centrada em quatro áreas de pesquisa: relações de trabalho, teoria institucional, organização industrial e economia da tecnologia. Nessas áreas, o embasamento teórico é dado pelos campos de Industrial Relations e pela Economia Evolucionária: Neoschumpeteriana e Neoinstitucionalista. Em relação ao primeiro, é feita uma descrição desse campo de estudo e a apresentação do modelo de análise de relações de trabalho de John T. Dunlop, tal como proposto originalmente na sua obra Industrial Relations Systems, publicada em 1958. Indicam-se as suas propriedades e também as suas limitações para tratar com a mudança em relações de trabalho em sentido evolutivo. É sobre esse modelo que se aplica os construtos teóricos daquelas outras duas correntes que compõem a Teoria Evolucionária para torná-lo, então, um Sistema de Relações de Trabalho evolutivo (SRT-e). O esforço teórico consiste em modificar o modelo de SRT dunlopiano para assimilar e adaptar os princípios da teoria da evolução de Darwin. Os princípios darwinianos de uma abordagem evolucionária são a ocorrência endógena ao modelo de: variedade, seleção e herança. Da Teoria Neoschumpeteriana se toma emprestado a concepção de concorrência schumpeteriana, da tecnologia como um determinante básico da dinâmica da economia capitalista, da firma como a instituição que introduz as novidades tecnológicas no sistema, bem como o conceito de paradigma tecno-econômico, para explicar como os avanços tecnológicos modificam o SRT-e. A Teoria Neoinstitucionalista contribui com o conceito de instituição, na sua influência na vida econômica e para dar efetividade às inovações que são lançadas na economia. É feita, então, uma junção de conceitos dessas duas correntes de modo a mostrar como é feita a co-evolução entre as tecnologias e as instituições das relações de trabalho. / This thesis provides an evolutionary industrial relations systems approach (SRT-e), which consists in proposing an analytical tool that allows to study the changes in industrial relations systems over time as an evolutionary process driven by technological advances. For this purpose, the SRT model developed by John Dunlop was taken as a base and modified to bring them into line with the contribution of the Evolutionary Theory. The change occurs towards making endogenous to the model the sources that generates variety in the SRT developed by Dunlop, through greater centrality of the firm, as the one that develops and introduces new technologies into the economy to gain competitive advantage in the process of market competition, and by changing the conception of the context of the industrial relations system. Therefore, the proposed change allows that the link between physical technologies, organizational routines (social technology), forms of regulation of labor relations contained in the rules (social technology) and the web of rules of the SRT (institutions) is established, consisting in the use of the "bridge" between technologies and institutions suggested by Richard Nelson. Based on the analysis tool of SRT-e, the theoretical effort of the thesis was also aimed to identify how the alignment between technological innovations of a new techno- economic paradigm, and labor relations institutions occurs. It was explored the idea of the “bridge”, as suggested by Richard Nelson, identifying from a theoretical point of view, how the match between technologies and the institutions of industrial relations occurs, which is one of the main alignments necessary to the full establishment of a new techno-economic paradigm, allowing to the full deployment of the economic development potential of a given country to be achieved. The thesis proposal is centered on four areas of research: industrial relations, institutional theory, industrial organization theory, and technological economy. In these areas, the theoretical basis comes from the fields of Industrial Relations and Evolutionary Theory: Neoschumpeterian and Neo-institutionalist theories. Regarding to the first one, it is made a description of this field of study and a presentation of the model of analysis of IRS, as originally proposed by John T. Dunlop in his book Industrial Relations Systems, published in 1958. It will be indicated its proprieties and limitations in dealing with change in an evolutionary sense. It is on this model that will be applied the theoretical constructs from the other two stream of economic thought (Neoschumpeterian and Neo- institutionalist) to make it, then, an evolutionary industrial relations systems (SRT-e). The theoretical effort consists in modifying the dunlopian SRT model to assimilate and to adapt the principles of Darwin's theory of evolution. The darwinian principles of an evolutionary approach are the occurrence of variety, selection and inheritance as being endogenous to the model. From Neoschumpeterian Theory, it borrows the concept of Schumpeterian competition, and technology as a basic determinant of the dynamics of the capitalist economy, and the firm as the institution that introduces technological innovations in the system. Another relevant concept used from that theory is the techno-economic paradigm, which is used to explain how the technological advances modify the SRT-e. The Neo-Institutionalist Theory contributes with the concept of institution, its influence on the economic life, and the way that it gave effectiveness to the innovations that are introduced into the economy. Then, it will be make a junction of concepts of these two currents of economic thoughts so as to show that there is a co-evolution between technologies and the institutions of industrial relations.
47

Uma abordagem evolucionária de sistemas de relações de trabalho : o processo de co-evolução entre tecnologias e as instituições do trabalho

Costa, Rodrigo Morem da January 2014 (has links)
Esta tese estabelece uma abordagem evolucionária de sistemas de relações de trabalho (SRT- e), a qual consiste em propor uma ferramenta analítica que possibilite estudar as mudanças em sistemas de relações de trabalho ao longo do tempo como um processo evolutivo movido pelos avanços tecnológicos. Para esse intuito, o modelo de SRT desenvolvido por John Dunlop foi tomado como base, sendo modificado para compatibilizá-lo com as contribuições da Teoria Evolucionária. A alteração foi feita no sentido de tornar endógena ao modelo as fontes de geração de variedade no SRT desenvolvido por Dunlop, através de uma maior centralidade da firma, como aquela que desenvolve e introduz novas tecnologias na economia para obter vantagem competitiva em seu processo de concorrência no mercado, e da alteração na concepção do contexto do sistema de relações de trabalho. Desse modo, a mudança proposta permite que o nexo entre tecnologias físicas, rotinas organizacionais (tecnologia social), formas de regulação das relações de trabalho constantes nas regras (tecnologia social) e a teia de regras do SRT-e (instituições) seja estabelecido, consistindo no uso da “ponte” entre tecnologias e instituições, conforme sugerida por Richard Nelson. Com base na ferramenta de análise de SRT-e, o esforço teórico da tese foi, também, o de identificar como ocorre o alinhamento entre as inovações tecnológicas de um novo paradigma tecno- econômico e as instituições das relações de trabalho. Para tanto, foi explorada a ideia da “ponte” proposta por Richard Nelson, identificando do ponto de vista teórico, como ocorre a compatibilização entre as tecnologias e as instituições das relações de trabalho, que se constitui em um dos principais alinhamentos ao pleno estabelecimento de um novo paradigma tecno-econômico, ao permitir a efetividade de exploração do potencial de desenvolvimento econômico de um dado país. A proposta da tese está centrada em quatro áreas de pesquisa: relações de trabalho, teoria institucional, organização industrial e economia da tecnologia. Nessas áreas, o embasamento teórico é dado pelos campos de Industrial Relations e pela Economia Evolucionária: Neoschumpeteriana e Neoinstitucionalista. Em relação ao primeiro, é feita uma descrição desse campo de estudo e a apresentação do modelo de análise de relações de trabalho de John T. Dunlop, tal como proposto originalmente na sua obra Industrial Relations Systems, publicada em 1958. Indicam-se as suas propriedades e também as suas limitações para tratar com a mudança em relações de trabalho em sentido evolutivo. É sobre esse modelo que se aplica os construtos teóricos daquelas outras duas correntes que compõem a Teoria Evolucionária para torná-lo, então, um Sistema de Relações de Trabalho evolutivo (SRT-e). O esforço teórico consiste em modificar o modelo de SRT dunlopiano para assimilar e adaptar os princípios da teoria da evolução de Darwin. Os princípios darwinianos de uma abordagem evolucionária são a ocorrência endógena ao modelo de: variedade, seleção e herança. Da Teoria Neoschumpeteriana se toma emprestado a concepção de concorrência schumpeteriana, da tecnologia como um determinante básico da dinâmica da economia capitalista, da firma como a instituição que introduz as novidades tecnológicas no sistema, bem como o conceito de paradigma tecno-econômico, para explicar como os avanços tecnológicos modificam o SRT-e. A Teoria Neoinstitucionalista contribui com o conceito de instituição, na sua influência na vida econômica e para dar efetividade às inovações que são lançadas na economia. É feita, então, uma junção de conceitos dessas duas correntes de modo a mostrar como é feita a co-evolução entre as tecnologias e as instituições das relações de trabalho. / This thesis provides an evolutionary industrial relations systems approach (SRT-e), which consists in proposing an analytical tool that allows to study the changes in industrial relations systems over time as an evolutionary process driven by technological advances. For this purpose, the SRT model developed by John Dunlop was taken as a base and modified to bring them into line with the contribution of the Evolutionary Theory. The change occurs towards making endogenous to the model the sources that generates variety in the SRT developed by Dunlop, through greater centrality of the firm, as the one that develops and introduces new technologies into the economy to gain competitive advantage in the process of market competition, and by changing the conception of the context of the industrial relations system. Therefore, the proposed change allows that the link between physical technologies, organizational routines (social technology), forms of regulation of labor relations contained in the rules (social technology) and the web of rules of the SRT (institutions) is established, consisting in the use of the "bridge" between technologies and institutions suggested by Richard Nelson. Based on the analysis tool of SRT-e, the theoretical effort of the thesis was also aimed to identify how the alignment between technological innovations of a new techno- economic paradigm, and labor relations institutions occurs. It was explored the idea of the “bridge”, as suggested by Richard Nelson, identifying from a theoretical point of view, how the match between technologies and the institutions of industrial relations occurs, which is one of the main alignments necessary to the full establishment of a new techno-economic paradigm, allowing to the full deployment of the economic development potential of a given country to be achieved. The thesis proposal is centered on four areas of research: industrial relations, institutional theory, industrial organization theory, and technological economy. In these areas, the theoretical basis comes from the fields of Industrial Relations and Evolutionary Theory: Neoschumpeterian and Neo-institutionalist theories. Regarding to the first one, it is made a description of this field of study and a presentation of the model of analysis of IRS, as originally proposed by John T. Dunlop in his book Industrial Relations Systems, published in 1958. It will be indicated its proprieties and limitations in dealing with change in an evolutionary sense. It is on this model that will be applied the theoretical constructs from the other two stream of economic thought (Neoschumpeterian and Neo- institutionalist) to make it, then, an evolutionary industrial relations systems (SRT-e). The theoretical effort consists in modifying the dunlopian SRT model to assimilate and to adapt the principles of Darwin's theory of evolution. The darwinian principles of an evolutionary approach are the occurrence of variety, selection and inheritance as being endogenous to the model. From Neoschumpeterian Theory, it borrows the concept of Schumpeterian competition, and technology as a basic determinant of the dynamics of the capitalist economy, and the firm as the institution that introduces technological innovations in the system. Another relevant concept used from that theory is the techno-economic paradigm, which is used to explain how the technological advances modify the SRT-e. The Neo-Institutionalist Theory contributes with the concept of institution, its influence on the economic life, and the way that it gave effectiveness to the innovations that are introduced into the economy. Then, it will be make a junction of concepts of these two currents of economic thoughts so as to show that there is a co-evolution between technologies and the institutions of industrial relations.
48

Uma abordagem evolucionária de sistemas de relações de trabalho : o processo de co-evolução entre tecnologias e as instituições do trabalho

Costa, Rodrigo Morem da January 2014 (has links)
Esta tese estabelece uma abordagem evolucionária de sistemas de relações de trabalho (SRT- e), a qual consiste em propor uma ferramenta analítica que possibilite estudar as mudanças em sistemas de relações de trabalho ao longo do tempo como um processo evolutivo movido pelos avanços tecnológicos. Para esse intuito, o modelo de SRT desenvolvido por John Dunlop foi tomado como base, sendo modificado para compatibilizá-lo com as contribuições da Teoria Evolucionária. A alteração foi feita no sentido de tornar endógena ao modelo as fontes de geração de variedade no SRT desenvolvido por Dunlop, através de uma maior centralidade da firma, como aquela que desenvolve e introduz novas tecnologias na economia para obter vantagem competitiva em seu processo de concorrência no mercado, e da alteração na concepção do contexto do sistema de relações de trabalho. Desse modo, a mudança proposta permite que o nexo entre tecnologias físicas, rotinas organizacionais (tecnologia social), formas de regulação das relações de trabalho constantes nas regras (tecnologia social) e a teia de regras do SRT-e (instituições) seja estabelecido, consistindo no uso da “ponte” entre tecnologias e instituições, conforme sugerida por Richard Nelson. Com base na ferramenta de análise de SRT-e, o esforço teórico da tese foi, também, o de identificar como ocorre o alinhamento entre as inovações tecnológicas de um novo paradigma tecno- econômico e as instituições das relações de trabalho. Para tanto, foi explorada a ideia da “ponte” proposta por Richard Nelson, identificando do ponto de vista teórico, como ocorre a compatibilização entre as tecnologias e as instituições das relações de trabalho, que se constitui em um dos principais alinhamentos ao pleno estabelecimento de um novo paradigma tecno-econômico, ao permitir a efetividade de exploração do potencial de desenvolvimento econômico de um dado país. A proposta da tese está centrada em quatro áreas de pesquisa: relações de trabalho, teoria institucional, organização industrial e economia da tecnologia. Nessas áreas, o embasamento teórico é dado pelos campos de Industrial Relations e pela Economia Evolucionária: Neoschumpeteriana e Neoinstitucionalista. Em relação ao primeiro, é feita uma descrição desse campo de estudo e a apresentação do modelo de análise de relações de trabalho de John T. Dunlop, tal como proposto originalmente na sua obra Industrial Relations Systems, publicada em 1958. Indicam-se as suas propriedades e também as suas limitações para tratar com a mudança em relações de trabalho em sentido evolutivo. É sobre esse modelo que se aplica os construtos teóricos daquelas outras duas correntes que compõem a Teoria Evolucionária para torná-lo, então, um Sistema de Relações de Trabalho evolutivo (SRT-e). O esforço teórico consiste em modificar o modelo de SRT dunlopiano para assimilar e adaptar os princípios da teoria da evolução de Darwin. Os princípios darwinianos de uma abordagem evolucionária são a ocorrência endógena ao modelo de: variedade, seleção e herança. Da Teoria Neoschumpeteriana se toma emprestado a concepção de concorrência schumpeteriana, da tecnologia como um determinante básico da dinâmica da economia capitalista, da firma como a instituição que introduz as novidades tecnológicas no sistema, bem como o conceito de paradigma tecno-econômico, para explicar como os avanços tecnológicos modificam o SRT-e. A Teoria Neoinstitucionalista contribui com o conceito de instituição, na sua influência na vida econômica e para dar efetividade às inovações que são lançadas na economia. É feita, então, uma junção de conceitos dessas duas correntes de modo a mostrar como é feita a co-evolução entre as tecnologias e as instituições das relações de trabalho. / This thesis provides an evolutionary industrial relations systems approach (SRT-e), which consists in proposing an analytical tool that allows to study the changes in industrial relations systems over time as an evolutionary process driven by technological advances. For this purpose, the SRT model developed by John Dunlop was taken as a base and modified to bring them into line with the contribution of the Evolutionary Theory. The change occurs towards making endogenous to the model the sources that generates variety in the SRT developed by Dunlop, through greater centrality of the firm, as the one that develops and introduces new technologies into the economy to gain competitive advantage in the process of market competition, and by changing the conception of the context of the industrial relations system. Therefore, the proposed change allows that the link between physical technologies, organizational routines (social technology), forms of regulation of labor relations contained in the rules (social technology) and the web of rules of the SRT (institutions) is established, consisting in the use of the "bridge" between technologies and institutions suggested by Richard Nelson. Based on the analysis tool of SRT-e, the theoretical effort of the thesis was also aimed to identify how the alignment between technological innovations of a new techno- economic paradigm, and labor relations institutions occurs. It was explored the idea of the “bridge”, as suggested by Richard Nelson, identifying from a theoretical point of view, how the match between technologies and the institutions of industrial relations occurs, which is one of the main alignments necessary to the full establishment of a new techno-economic paradigm, allowing to the full deployment of the economic development potential of a given country to be achieved. The thesis proposal is centered on four areas of research: industrial relations, institutional theory, industrial organization theory, and technological economy. In these areas, the theoretical basis comes from the fields of Industrial Relations and Evolutionary Theory: Neoschumpeterian and Neo-institutionalist theories. Regarding to the first one, it is made a description of this field of study and a presentation of the model of analysis of IRS, as originally proposed by John T. Dunlop in his book Industrial Relations Systems, published in 1958. It will be indicated its proprieties and limitations in dealing with change in an evolutionary sense. It is on this model that will be applied the theoretical constructs from the other two stream of economic thought (Neoschumpeterian and Neo- institutionalist) to make it, then, an evolutionary industrial relations systems (SRT-e). The theoretical effort consists in modifying the dunlopian SRT model to assimilate and to adapt the principles of Darwin's theory of evolution. The darwinian principles of an evolutionary approach are the occurrence of variety, selection and inheritance as being endogenous to the model. From Neoschumpeterian Theory, it borrows the concept of Schumpeterian competition, and technology as a basic determinant of the dynamics of the capitalist economy, and the firm as the institution that introduces technological innovations in the system. Another relevant concept used from that theory is the techno-economic paradigm, which is used to explain how the technological advances modify the SRT-e. The Neo-Institutionalist Theory contributes with the concept of institution, its influence on the economic life, and the way that it gave effectiveness to the innovations that are introduced into the economy. Then, it will be make a junction of concepts of these two currents of economic thoughts so as to show that there is a co-evolution between technologies and the institutions of industrial relations.
49

Information networks among species:adaptations and counter-adaptations in acquiring and hiding information

Loukola, O. (Olli) 06 May 2014 (has links)
Abstract Social information use is a widespread phenomenon across the animal kingdom and it affects various important aspects of animal behaviour. Animals observe and copy the behaviour of conspecifics and other species on the same trophic level in their own decision-making, e.g., in habitat or mate choice. Copying is adaptive only when it is selective. Thus, it would be important to understand when and which individuals should copy others, and which individuals they choose to copy and what are the consequences of social information use. In this thesis, I experimentally study these questions in wild animals living in natural conditions. By simulating arbitrary preference of great tits (Parus major), I demonstrated that the portrayed fitness does not affect the nest site choices of conspecifics, but the tit pairs with an old male prefer the nest site choices of good and poor conspecifics. Social information use among tits appears to be age- and sex-dependent. Pied flycatchers (Ficedula hypoleuca), however, selectively copy or reject a novel nest site feature preference (symbol attached to the nest box) of great tits experimentally manipulated to exhibit high or low fitness (clutch size), respectively. By offering pied flycatchers choice in nest boxes with alternative contents, I showed that nest take-overs of flycatchers are not a form of social information use, but seem to result from the reduced building effort required. Furthermore, by conducting a decoy and playback experiment, I showed that great tits covered eggs more efficiently in the presence of pied flycatchers. One function of egg covering behaviour seems to be a counter-adaptation to reduce information parasitism by pied flycatchers. My results demonstrate that the social transmission of behaviours across species can be highly selective in response to observed fitness, plausibly making the phenomenon adaptive. In contrast with the current theory of species coexistence, overlap between realized niches of species could dynamically increase or decrease, depending on the observed success of surrounding individuals. The social information revealed by success and behaviour of animals is a resource that can be used or concealed. It is a new kind of evolutionary and ecological factor which may affect the formation of ecosystems and species coevolution. / Tiivistelmä Sosiaalinen informaationkäyttö on yleinen ilmiö eläinkunnassa, ja sitä tavataan aina hyönteisistä valaisiin. Yksilöt tarkkailevat ja kopioivat sekä lajitovereiden että toisen ekologialtaan samankaltaisen lajin yksilöiden käyttäytymistä erilaisissa tilanteissa, kuten pesäpaikan tai parittelukumppanin valinnassa. Sosiaalinen informaationkäyttö on adaptiivista ainoastaan ollessaan valikoivaa. Siksi on tärkeää selvittää kenen, koska ja ketä kannattaa kopioida, ja mitä ekologisia ja evolutiivisia seurauksia siitä koituu informaation lähteelle ja käyttäjälle. Väitöskirjassani tutkin kokeellisesti informaation hankkijan (kirjosieppo Ficedula hypoleuca) valikoivaa kopioimista ja siitä mahdollisesti johtuvaa informaation lähteen (talitiainen Parus major) vasta-adaptaatiota luonnonoloissa. Symbolikokeilla selvitin, että talitiaisten lajinsisäinen kopiointi on iästä ja sukupuolesta riippuvaa, mutta informaationlähteen havaittu kelpoisuus ei vaikuta kopioinnin todennäköisyyteen. Kirjosiepot puolestaan kopioivat valikoivasti keinotekoisesti luotuja tiaisten mieltymyksiä pesäpönttöön kiinnitettyjä symboleja kohtaan, riippuen tiaisten havaitusta manipuloidusta kelpoisuudesta (munamäärästä pesässä). Siepot kopioivat tiaisia, joiden pesässä on paljon munia (13 munaa), ja rejektoivat tiaisia (valitsevat vaihtoehtoisen symbolin), joilla munia on vähän (5 munaa). Tarjoamalla kirjosiepoille vaihtoehtoisia pesäpönttöjä osoitin, että sieppojen luontainen mieltymys vallata ja rakentaa pesänsä toisten pesien päälle ei ole sosiaalisen informaationkäytön muoto, vaan se näyttää olevan pesänrakennuksen kustannusten minimointia. Playback-kokeilla osoitin, että talitiaisten munienpeittelykäyttäytymisellä on useita funktioita. Se on vasta-adaptaatio kirjosiepon informaatioloisintaa vastaan ja toimii mahdollisesti suojana kylmää vastaan. Väitöskirjani tulokset osoittavat, että eläinten käyttäytymisen paljastama sosiaalinen informaatio on resurssi, jota voidaan hyödyntää tai salata. Se on myös uudenlainen ekologinen ja evolutiivinen tekijä, joka vaikuttaa eliöyhteisöjen muodostumiseen ja lajien koevoluutioon. Lajienvälinen valikoiva sosiaalinen informaationkäyttö -hypoteesi haastaa nykyisen koevoluutioteorian. Se ennustaa, että informaatiota hyödyntävän lajin ja informaationlähteen ominaisuudet voivat joko samankaltaistua tai erilaistua, informaationlähteen havaittavasta menestyksestä riippuen.
50

Special Nature Reserve Area Destination Development : Path dependence and co-evolution in the case study of "Carska Bara", Vojvodina Province, Serbia

Martinović, Dunja January 2017 (has links)
The study focuses on the development path of a tourism destination area centered around a special nature reserve and adjacent rural communities in the northern part of Serbia. Utilizing evolutionary economic geography (EEG) as an increasingly present theoretical and conceptual framework in the studies of tourism, this research project employs key EEG concepts of ‘path dependence’ and ‘co-evolution’. ‘Path dependence’ examines different social, economic, institutional and sectoral factors that direct, propel and/or hinder destination development, while ‘co-evolution’ analyzes causal and relational exchanges of stakeholders within and associated with the destination. The objective of this study is to trace developmental and relational trajectories of the nature reserve, tourism enterprises in its vicinity, and the place and role of public sector in these processes. The study, therefore, aims to analyze: (1) how the concept of ‘path dependence’ applies to the tourism development path of the nature reserve; (2) the dynamics of co-evolutionary and relational exchange processes in the nature reserve destination area, namely those occurring between actors operating in both public and private sectors. The two combined EEG approaches, previously not applied within the outlined geographical context, serve to illustrate and explain overall development mechanisms within a tourism destination, relevant economically, socio-culturally as well as environmentally for its region and on the tourism market of Serbia. When methodology is concerned, the study is in form of a case study, with primary data drawn from semi-structured, in-depth interviews and supported with complementary data from relevant scientific articles, government documents, web sites and other publications. The study findings show that the nature reserve in its tourism growth displays a path dependence determined by two seemingly diverging factors: (1) rules and regulations pertaining to protected areas such as nature reserves dictate tourism development and (2) the reserve management entrepreneurial skills play a noteworthy role in shaping its tourism growth. Apart from path dependence, the tourism development path associated with the nature reserve displays path plasticity, which represents a new direction in tourism growth based on the existing infrastructural and managerial framework. Moreover, the study outcomes indicate that levels, directions and intensity of co-evolutionary and relational exchanges among all stakeholders included demonstrate several different patterns. While there is detectable relationship between the nature reserve and most local tourism-related stakeholders, relationships among local stakeholders themselves are rather uneven. Similar patterns are found regarding the involvement of public sector. Public sector is closely linked with the nature reserve, however, its association with other tourism stakeholders in the destination area is uneven.  These findings support the idea that each destination area stands as a unique and complex entity, with various endogenous and exogenous factors shaping its growth.

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